The Response Characteristic of Peripheral Chemoreceptors and Their Physiological Relevance

Abstract

In 1960, Yamamoto suggested that arterial pCO₂ oscillations play a role in the control of respiration. Within breath fluctuations of blood gas tensions of pO₂ (Purves 1966), pCO₂ (Plaas-Link et al. 1976) and pH (Band et al. 1969) have been measured. It remains unclear how the peripheral chemoreceptors react to the small and quick changes of pCO₂. Several authors observed different receptor characteristics according to their technique of measurement. In the present study we tried to approximate the experimental conditions to natural conditions in meeting the following requirements:

• 1. The solution to perfuse the receptor should be blood containing the natural red cell fraction. (Fitzgerald et al. 1968, Ponté and Purves 1974).

• 2. The amplitudes of the changes in the solutions should be small, because they will influence the response characteristic of the receptors. (Ponté and Purves 1974).

• 3. The sinus nerves should be intact, because efferent control of the chemoreceptor affects the chemoreceptor response. (Majcherczyk and Willshaw 1973, Goodman 1974).

• 4. The experiments should be done under normoxia, because hypoxia or hyperoxia will affect the neural discharge of the receptor. (Black and Torrance 1967, Gray 1968, Fitzgerald and Parks 1971, Gehrich and Moore 1973).